Navigation - Routes

 Routes 

Source Code

import 'package:flutter/material.dart';


void main() {
  runApp(  MaterialApp(
    title:" Routes ",
    home:Scaffold(appBar: AppBar(title: Text(' Routes ',),),
      body: Material(
        child: Center(
          child:
          RoutesExample()
          ,
        ),
      ) ,
    ),
  ));
}





class RoutesExample extends StatelessWidget {
  const RoutesExample({Key? key}) : super(key: key);

 
  static const kRouteName = '/RoutesExample';

  @override
  Widget build(BuildContext context) {
    debugPrint('RouteName=${ModalRoute.of(context)?.settings.name}');
    return Scaffold(
      appBar: AppBar(
        automaticallyImplyLeading: false,
        title: const Text('Page 1'),
      ),
      body: Center(
        child: ElevatedButton(
          onPressed: () {
            // Navigator maintains a stack-like structure of pages. Jumping
            // between routes is by push/pop of Navigator.
            Navigator.push(context, _PageTwo());
          },
          child: const Text('Go to page two'),
        ),
      ),
    );
  }
}

// <void> means this route returns nothing.
class _PageTwo extends MaterialPageRoute<void> {
  _PageTwo()
      : super(builder: (BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Page 2'),
        elevation: 1.0,
      ),
      // *Note*: use a Builder instead of directly giving the body, so
      // that Scaffold.of(context) won't throw exception, c.f.
      // https://stackoverflow.com/a/51304732.
      body: Builder(
        builder: (BuildContext context) => Center(
          child: ElevatedButton(
            onPressed: () {
              // Navigator.push<T> returns a Future<T>, which is the
              // return value of the pushed route when it's popped.
              Navigator.push<String>(context, _PageThree())
                  .then((returnVal) {
                if (returnVal != null) {
                  ScaffoldMessenger.of(context).removeCurrentSnackBar();
                  ScaffoldMessenger.of(context).showSnackBar(
                    SnackBar(
                      content: Text('You clicked: $returnVal'),
                      action: SnackBarAction(
                        label: 'OK',
                        onPressed: () {},
                      ),
                    ),
                  );
                }
              });
            },
            child: const Text('Go to page 3'),
          ),
        ),
      ),
    );
  });
}

// MaterialPageRoute<String> returns a Future<String>.
class _PageThree extends MaterialPageRoute<String> {
  _PageThree()
      : super(builder: (BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Last page'),
        elevation: 2.0,
        actions: <Widget>[
          IconButton(
            icon: const Icon(Icons.close),
            onPressed: () {
              Navigator.pop(context);
            },
          ),
        ],
      ),
      body: Padding(
        padding: const EdgeInsets.all(32.0),
        child: ListView(
          children: <Widget>[
            ListTile(
              leading: const CircleAvatar(child: Text('1')),
              title: const Text('user1@example.com'),
              onTap: () => Navigator.pop(context, 'user1@example.com'),
            ),
            ListTile(
              leading: const CircleAvatar(child: Text('2')),
              title: const Text('user2@example.com'),
              onTap: () => Navigator.pop(context, 'user2@example.com'),
            ),
            ListTile(
              leading: const CircleAvatar(child: Text('3')),
              title: const Text('user3@example.com'),
              onTap: () => Navigator.pop(context, 'user3@example.com'),
            ),
            const Divider(),
            MaterialButton(
              onPressed: () {
                // Pops until reaching a route with that route name.
                Navigator.popUntil(
                  context,
                  ModalRoute.withName(RoutesExample.kRouteName),
                );
              },
              child: const Text('Go home'),
            ),
          ],
        ),
      ),
    );
  });
}